1. Field of the Invention
This invention relates to an apparatus for regeneration of a particulate filter disposed in an exhaust passage that removes particulates out of an exhaust gas in a diesel engine and the like.
2. Related Art of the Invention
There is known a particulate filter that removes particulates out of an exhaust gas in a diesel engine. The particulate filter needs to remove deposited particulates for regeneration thereof before the particulates are deposited excessively. Removal of the particulates is carried out in general by burning the particulates.
A Japanese Unexamined Patent Publication No. 05-312022 discloses that a starting point of regeneration period of the particulate filter is made considering an amount of unburned particulates remaining on the particulate filter after the particulate filter has been regenerated previously.
In this Publication, the unburned, remaining amount of the particulates is estimated by a fuzzy theory based upon a filter temperature detection signal from a temperature sensor disposed respectively at a center and a periphery of the particulate filter.